This invention relates to photographic materials. It particularly relates to photographic base materials and the formation of a mechanically assembled picture utilizing a brace.
In the formation of color paper it is known that the base paper has applied thereto a layer of polymer, typically polyethylene. This layer serves to provide waterproofing to the paper, as well as providing a smooth surface on which the photosensitive layers are formed. The formation of a suitably smooth surface is difficult requiring great care and expense to ensure proper laydown and cooling of the polyethylene layers. Such a smooth surface requires a great deal of care and expense associated with chill rolls. There is a need for a photographic color print material that has a polyethylene surface but does not require chill rolls for the formation of a glossy surface.
In photographic papers the polyethylene layer also serves as a carrier layer for titanium dioxide and other whitener materials as well as tint materials. It would be desirable if the colorant materials rather than being dispersed throughout the polyethylene layer could be concentrated nearer the surface of the layer where they would be more effective photographically.
In the formation of photographic and other imaging elements it is known in the art to coat or apply layers of polymer to or to laminate biaxially oriented sheets of polymer to a base substrate such as paper or polyester. It is further known in the art as disclosed in U.S. Pat. No. 4,355,099 to provide a silver halide layer on a clear film, expose, develop, process and then to post laminate using an adhesive to a light reflective base. While such a composite structure has a number of advantages, it is very difficult and cumbersome to apply an adhesive, cure it and then stick two webs together. There remains a need to provide an imaging element with a thin protective polymer sheet with an image receiving layer that can be attached to a reflective base without the use of expensive, messy adhesive.
In U.S. Pat. No. 5,663,023 a two part system for xerography and ink is disclosed. The first part provides a clear substrate with a reverse reading image that is imaged and then joined with a reflective base that has been pre coated with an adhesive. While this technique overcomes some of the difficulties of applying an adhesive at the time of image formation by using a pre-coated substrate, there are additional problems and difficulties with joining the two substrates without creases. Furthermore even pre-coated adhesives a still messy and may contaminate the work area and render the image useless because of the contamination problems. There remains a need to provide an imaging element with thin clear polymer over the image that can be attached to a reflective or even transparent base without the use of expensive, messy adhesives.
In U.S. Pat. No. 5,866,282 it is proposed to attach sheets of biaxially oriented polymer to a base substrate for photographic use, and in U.S. Pat. No. 5,888,714 it is proposed to use an adhesive such as metallocene catalyzed ethylene plastomers for bonding biaxially oriented polyolefin sheets. Both these inventions provide excellent print materials and are able to adhere the biaxially oriented sheets to the base substrate. The base substrate provides sufficient stiffness to the support for conveyance through the various coating and processing machines. One drawback of this system is the expense of having to adhere polymer sheets to a base substrate and then carry the added weight and thickness throughout the manufacturing and photofinishing process. The added thickness put limitations on the length of rolls requires frequent roll changes, which results in added waste and expense. There remains a need to provide a substantially thin imaging support that does not require it to be adhered to a thick base substrate.
Photographic materials have been known for use as prints for preserving memories for special events such as birthdays and vacations. They also have been utilized for large display materials utilized in advertising. These materials have been known as high quality products that are costly and somewhat delicate, as they would be easily defaced by abrasion, water, or bending. Photographs are traditionally placed in frames and photo albums in view of their fragile and delicate nature, as well as their value. They are considered luxury items for the consumers to preserve a record of important events in their lives. Photo albums and picture frames do not allow prints to be handled and viewed in a convenient or friendly manner. There remains a need to provide a convenient and friendly format for images to be shared with a number of people without fear of irreversible damage.
Prior art photographic reflective materials typically contain cellulose fiber paper to provide support for the imaging layers. While paper is an acceptable support for the imaging layers, providing a perceptually preferred feel and look to the photograph, paper does present a number of manufacturing problems which reduce the efficiency at which photographic paper can be manufactured. Problems include those such as processing chemistry penetration into the edges of the paper, paper dust as photographic paper is slit, punched and chopped, and as loss of emulsion hardening efficiency because of the moisture gradient that exists between the photographic emulsion and the paper. It would be desirable if a reflective image could be formed without the use of cellulose paper.
In reflective photographic papers there is a need to protect the imaging layers from scratches, fingerprints, and stains. Current photographic reflective papers use a gelatin overcoat to protect the imaging layers. While the gelatin does provide some level of protection, it can easily be scratched reducing the quality of the image. Further, fingerprints or stains caused by common household liquids such as coffee, water, or fruit juice can easily stain and distort images. Wiping the images while wet causes undesirable distortion to the gelatin overcoat. Post photographic processing equipment exists that provides a protective coating to the imaging layers. Typically consumer images are individually coated or laminated with a polymer to provide protection to the image layers. A common example is photographic identification badges that are typically laminated with a clear polymer sheet to provide protection to the image on the identification badge. Post processing application of a protective layer is expensive, as it requires an additional step in the preparation of the reflective print and additional materials to provide the overcoat. It would be desirable if a reflective photographic image could be formed with a protective coating over the developed image layers that could be efficiently applied.
Typically, photographic reflective imaging layers are coated on a polyethylene coated cellulose paper. While polyethylene coated cellulose paper does provide an acceptable support for the imaging layers, there is a need for alternate support materials such as polyester or fabric. The problem with alternate, nonpaper supports is the lack of robustness in photographic processing equipment to mechanical property changes in supports. The photographic processing equipment will not run photographic materials that have significantly different mechanical properties than prior art photographic materials. It would be desirable if a reflective photographic image could be efficiently formed on alternate supports.
In the consumer industry materials are placed in packages as a means of protection or preserving the quality of the delicate products. Photographs and images are a very delicate product but are not traditional protected from handling damage, spills, fingerprints and other abuses. In some application the image may be overlaminated with a clear polymer sheet, but once again, the overlaminate sheet must be adhesive coated prior to application to the image. These overlaminates create problems with curl and torsional strain on the image structure that render them undesirable. There remains a need to provide a print with protection without curl and other problems.
Photographic images are typically produced on a thick polymer coated paper base. The paper base used for photographic prints is very expensive and must be very pure and free of materials that are photoactive and resistant to photo processing chemicals. There remains a need for a photographic print material that is not limited by these and other design limitations.
It is an object of the invention to provide improved imaging elements.
It is another object to provide an imaging element that does not need to be adhered to a thick base.
It is a further object to provide images that are not easily damaged.
It is an additional object of this invention to provide an image that is sealed from the environment.
These and other objects of the invention are accomplished by a mechanically assembled picture comprising at least one image element comprising an image on a thin polymer sheet, a brace, and a transparent polymer sheet overlaying said image and brace, wherein said transparent sheet mechanically holds said image to said brace.
The invention provides improved image protection. The invention includes a means to join a base substrate to an image without environmental protection without the use of expensive and messy adhesives. This invention provides an imaging element with a brace that makes a pleasing image for the consumer.